Theoretical Analysis of Some Ground State and Optical Properties of Impurity F Centers

Comparisons with experimental data are used to assess calculations on F‐type centers, based on an approximate pseudopotential model, using flexible symmetry‐adapted variational wave functions. Moderate success is obtained for optical absorption of the linear F B center in KCI:Na and RbCI:Na, and for the triangular F B center in KCI:Na. Satisfactory results for nearest‐neighbor isotropic hyperfine interactions of the F A center ground state in KBr:Li are obtained only from point‐ion wave functions, although to describe adequately optical absorption of the F and F A (Li) centers in KBr requires that the ion‐size correction must be included. Luminescence from the type II F A center in KCI:Li is also found to require the point‐ion approximation, including angular momentum components l > 1.